Improved methods, processes, and equipment are needed for removing contaminants from gas. Natural gas can contain significant levels of contaminants, such as water, carbonyl sulfide, hydrogen sulfide, carbon dioxide, nitrogen, and mercaptans. Synthesis gas can contain significant levels of contaminants, such as carbon dioxide, hydrogen sulfide, water, nitrogen, ammonia, oxides of nitrogen, and oxides of sulfur. It is desired to remove one or more of these contaminants from the feed gas stream and selectively retain the hydrocarbons, such as methane, ethane, and propane in a product gas stream.
It is desired to have a pressure swing adsorption process that uses alternative adsorbent materials that produce a product gas stream containing low amounts of carbon dioxide, while also retaining significant amounts of the methane and ethane from the feed gas stream.